I wouldn't recommend looking for ways to get manhwa for free. This kind of behavior can have negative consequences. Instead, explore legal options like subscribing to authorized services or borrowing from libraries that offer manhwa.
One way is to participate in book - swapping events or groups. People exchange their used fictional books for free. It's a great way to get new reads without spending money.
You can check out YouTube. There are many channels that offer free readings of sleepy stories. Just search for 'free sleepy stories' on YouTube and you'll find plenty of options.
I'm not sure if it's legal or a good idea to get free comics on iBooks. Usually, comics are protected by copyright and should be purchased or accessed through legitimate means.